Abrupt Breathlessness: Pneumocystis jirovecii Pneumonia Associated with Inebilizumab in Neuromyelitis Optica Spectrum Disorder: A Case Report and Literature Review

Xueqin Chen,1,* Jia Wang,1,* Caifeng Chen,2,* Jundan Wang,1 Lei Du,1 Wenxin Qin,1 Ziyu Xu,1 Lei Liu,3 Xiude Qin,4 Fanxin Kong4 1The Fourth Clinical Medical College, Guangzhou University of Chinese Medicine, Shenzhen, People’s Republic of China; 2Department of Traditional Chinese Medicine, The Fifth Medical Center, Chinese PLA General Hospital, Beijing, People’s Republic of China; 3Infectious Diseases Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, People’s Republic of China; 4Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lei Liu, Infectious Diseases Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, Guangdong, 518033, People’s Republic of China, Email [email protected] Fanxin Kong, Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, Guangdong, 518033, People’s Republic of China, Email [email protected]: Opportunistic infections pose significant challenges in patients undergoing immunosuppressive treatment for autoimmune disorders. Neuromyelitis optica spectrum disorder (NMOSD) is a rare disabling autoimmune condition requiring both acute attack management and long-term relapse prevention. B-cell depleting therapies, such as inebilizumab have demonstrated efficacy in reducing relapse rates and disability progression in NMOSD. Here, we present the first known NMOSD case who developed Pneumocystis jirovecii pneumonia following maintenance therapy with inebilizumab, showing a probable association (Naranjo score=6). We explored the underlying mechanisms linking B-cell depletion to Pneumocystis jirovecii, including antibody-dependent and immunomodulatory pathways. Furthermore, we provided an overview of Pneumocystis jirovecii pneumonia in autoimmune central nervous system disorders and summarized its clinical features, previous medication use, and prognostic factors. We advocate for risk-adapted prophylaxis to reduce morbidity and mortality associated with opportunistic infections in NMOSD.Keywords: opportunistic infections, drug safety monitoring, immunosuppressive therapy, antimicrobial prophylaxis